ENDOCARDITIS

inflammation of the heart lining, or endocardium. The inflammation may be associated with a noninfectious disease or may be caused by infection with any of a number of organisms, including bacteria and fungi. The site of the infection is usually the lining of the heart valves. Traditionally, infective endocarditis was classified as acute or subacute; more recently it has been classified by causative organism. The variety traditionally identified as acute usually results from severe infection with a well-known disease organism, such as Staphylococcus aureus (which is responsible for boils and abscesses) or Neisseria gonorrhoeae (the organism that causes gonorrhea). This form of infectious endocarditis develops rapidly, with fever, sweating, chills, pain in and swelling of the joints, weakness, loss of appetite and weight, visual disturbances, recurrent nosebleeding, frequent bruising, symptoms of heart failure, and a general feeling of ill health. Clumps of bacteria may break loose from the valve and enter the circulation, blocking the blood flow at some point. Petechiae, minute specks of colour from the bleeding of small blood vessels, may appear in the skin, in the mucous membrane lining the mouth or the throat, or in the conjunctivas. Subacuteor chronicendocarditis is usually caused by bacteria that do not cause disease except in tissues that are already weakened; thus, the chronic form may attack hearts weakened by congenital defects or previous infection. Bacterial endocarditis is usually treated by long-continued administration of bactericidal antibiotics, particularly some form of penicillin. Nonbacterial thrombotic endocarditis is an inflammation of unknown cause marked by the growth of blood clots along the closure lines of the heart valves. Symptoms include nosebleeds, bleeding of the gums, pain in the joints, fever, and a heart murmur during systole (heart contraction). Endocarditis also may be a feature of systemic lupus erythematosus, a disease of unknown cause that affects the connective tissues and may invade any organ of the body.